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Be humble for you are made of dung. Be noble for you are made of stars

“Be humble for you are made of dung. Be noble for you are made of stars.”

Indeed, everything is made of elements, as this Serbian proverb articulates. Of the 118 elements in the periodic table, approximately 25 are represented in biology. Living things use their genomic abilities to acquire these elements from the environment and allocate them to various functions that enable them to survive and reproduce. If the genome is the blueprint, then the elements represent the brick and mortar. Genomic ability without sufficient supply of necessary elements is useless, and vice versa. How does life strike a balance? Answers to this fundamental question is perhaps more important today than ever before, as anthropogenic activities are drastically altering the supplies of most of the elements represented in biology.

My research group has studied how a tiny crustacean (Daphnia) that live in North American lakes mitigates human alterations to the supply of key elements. Daphnia produce resting eggs that are preserved in lake sediments for centuries allowing us to compare the genetics and physiology of ancient (“resurrected”) and extant individuals. We have found strong correlations between the advent of industrialized agriculture in North America (~mid-1800s) which drastically changed the supply of several elements, and the genetics and physiology of Daphnia populations. Of course, Daphnia inhabit Finnish lakes as well. Several of these lakes were highly impacted by nutrient pollution until the 1970s, after which stringent Finnish environmental policies have resulted in marked restoration. My Fulbright sabbatical visit to the University of Jyvaskyla was originally planned to study how the genetics and physiology of Daphnia in such lakes has changed over time. We are in the process of reconstructing the genetic histories of Daphnia from two such lakes. While such reconstruction of genetic and physiological history is a unique and exciting way to understand the consequences of global environmental change, at its heart, it is a somewhat less rigorous, correlative exercise. But that’s the best we can do as we are unable to travel back in time and directly observe evolutionary dynamics to determine causation!

During the course of my sabbatical visit, I was exposed to a powerful approach that enables us to directly observe evolution - a field called experimental evolution. Here, scientists study rapidly growing microorganisms such as bacteria over a few weeks that can represent thousands of generations. For reference, if we assume a human generation is 20 years, about 10,000 generations separates us from our earliest known modern human ancestors (~200,000 years ago). My hosts and I have utilized this approach to test how a rapidly growing bacteria (Serratia) evolves under varying elemental supply environments (mimicking biogeochemical changes over the past few decades). The results are already rolling in, and very promising. Regardless of the outcome of this particular experiment, this impromptu endeavor has been immensely rewarding. I would say my 5-month Fulbright sabbatical visit has enriched my knowledge base as much, if not more than the 5 years I spent in doctoral school! Last but not least, the Fulbright fellowship enabled me to bring my young family along. Their experiences in Finland will no doubt shape their lives and the lives of others they interact with. The impact of which outweighs my own intellectual growth - which is precisely the spirit of the Fulbright Foundation.

Punidan Jeyasingh, 2016-2017 U.S. Fulbright Scholar to the University of Jyväskylä